French manicure + flats. Lace cami dress + t-shirt - mixing and matching classy with casual. I love to look at details and play around with them in my outfits (when I get time). I love how the white lines of the dress matches with the french manicure. Some of them appears in the print of the t-shirt. The bold strap of the flats resembles the wide belt and the horizontal line of the t-shirt.
 This trick - matching details, always works and can turn even a casual outfit into a chic one! It just looks like you have really thought of your outfit or have gone great lengths to find perfectly matching shoes and bag.  I would usually play around with 2-3 tones, match my nails with details in the outfit, or use a lipstick that shows up somewhere in my look and so on... 
In this outfit,  I actually tucked the cami dress under the belt making it look as skirt. Just because I felt like I need to accent the waist and it just gave a better over all feel. See, pretty casual, but eye-catching!

ZAFUL The 1975 T-shirt Black
NEW LOOK Black Suede Mules
MANGO Black Cami dress (similar)
MANGO Floral Cami dress (similar)
ZAFUL Black Striped Dresses